The present invention relates to liquid detergent compositions suitable for hand dishwashing comprising one or more polymeric suds volume and suds duration enhancers. The polymeric suds enhancers suitable for use in the compositions of the present invention comprise cationic, anionic, and noncharged monomer units, or units having mixtures thereof, wherein said polymers have an average cationic charge density from about 0.05 to about 5 units per 100 daltons molecular weight at a pH of from about 4 to about 12. The present invention further relates to methods for providing enhanced suds volume and suds duration during hand washing.
Liquid detergent compositions which are suitable for hand dishwashing must satisfy several criteria in order to be effective. These compositions must be effective in cutting grease and greasy food material and once removed, must keep the greasy material from re-depositing on the dishware.
The presence of suds in a hand dishwashing operation has long been used as a signal that the detergent continues to be effective. However, depending upon the circumstances, the presence of suds or the lack thereof, has no bearing upon the efficacy of liquid detergents. Therefore, the consumer has come to rely upon a somewhat erroneous signal, the lack or absence of soap suds, to indicate the need for additional detergent. In many instances the consumer is adding an additional amount of detergent far in excess of the amount necessary to thoroughly clean the dishes. This wasteful use of detergent is especially true in hand dishwashing since the soiled cooking articles are usually cleaned in a xe2x80x9cwashing difficultyxe2x80x9d queue, for example, glasses and cups, which usually do not contact greasy food, are washed first, followed by plates and flatware, and finally pots and pans which contain the most residual food material and are usually, therefore, the xe2x80x9cgreasiestxe2x80x9d.
The lack of suds in the dishwater when pots and pans are usually cleaned, together with the visual inspection of the amount of residual food material on the cookware surface, typically compels the consumer to add additional detergent when a sufficient amount still remains in solution to effectively remove the soil and grease from the dishware or cookware surface. However, effective grease cutting materials do not necessarily produce a substantial amount of corresponding suds.
Accordingly, there remains a need in the art for liquid dishwashing detergents useful for hand washing dishware which have an enduring suds level while maintaining effective grease cutting properties. The need exists for a composition which can maintain a high level of suds as long as the dishwashing composition is effective. Indeed, there is a long felt need to provide a hand dishwashing composition which can be use efficiently by the consumer such that the consumer uses only the necessary amount of detergent to fully accomplish the cleaning task.
The present invention meets the aforementioned needs in that it has been surprisingly discovered that polymeric materials having the capacity to accommodate a positive charge character, negative charge character, or zwitterionic character have the capacity to provide liquid hand wash detergent compositions with extended suds volume and suds duration benefits.
A first aspect of the present invention relates to liquid detergent compositions having increased suds volume and suds retention suitable for use in hand dishwashing, said compositions comprising:
a) an effective amount of a polymeric suds stabilizer, said stabilizer comprising:
i) units capable of having a cationic charge at a pH of from about 4 to about 12;
provided that said suds stabilizer has an average cationic charge density from about 0.05 to about 5 units per 100 daltons molecular weight at a pH of from about 4 to about 12;
b) an effective amount of a detersive surfactant; and
c) the balance carriers and other adjunct ingredients;
provided that a 10% aqueous solution of said detergent composition has a pH of from about 4 to about 12.
The present invention further relates to methods for providing increased suds retention and suds volume when hand washing dishware. These and other objects, features and advantages will become apparent to those of ordinary skill in the art from a reading of the following detailed description and the appended claims.
All percentages, ratios and proportions herein are by weight, unless otherwise specified. All temperatures are in degrees Celsius (xc2x0 C.) unless otherwise specified. All documents cited are in relevant part, incorporated herein by reference.